Light emitting device including light emitting unit arranged in a tube

ABSTRACT

A light-emitting device includes a carrier with a first surface and a second surface opposite to the first surface; and a light-emitting unit disposed on the first surface and configured to emit a light toward but not passing through the first surface. When emitting the light, the light-emitting device has a first light intensity above the first surface, and a second light intensity under the second surface, a ratio of the first light intensity to the second light intensity is in a range of 2˜9.

RELATED APPLICATION

This application is a continuation of U.S. application Ser. No.15/217,202, titled “Light emitting device including light emitting unitarranged in a tube”, and filed Jul. 22, 2016, which claims priority toand the benefit of Taiwan Application Serial Number 104123920 filed onJul. 23, 2015, which is incorporated herein by reference in itsentirety.

TECHNICAL FIELD

The present disclosure relates to a light-emitting device, and inparticular to a light-emitting device having an optic structure.

DESCRIPTION OF THE RELATED ART

The light-emitting diodes (LEDs) of the solid-state lighting elementshave the characteristics of low power consumption, long operationallife, small volume, quick response and good opto-electrical propertylike light emission with a stable wavelength so the conventionallighting fixtures are gradually replaced by the LEDs.

Although the filament made of the light-emitting diodes (LED filament)has been applied to the LED bulbs gradually recently, the fabricationcost and the lighting efficiency of the LED filament still need to beimproved. Furthermore, making the light field of the LED filamentomni-directional and dealing with the issue of the heat dissipation arestill under development.

SUMMARY OF THE DISCLOSURE

A light-emitting device includes a carrier with a first surface and asecond surface opposite to the first surface; and a light-emitting unitdisposed on the first surface and configured to emit a light toward butnot passing through the first surface. When emitting the light, thelight-emitting device has a first light intensity above the firstsurface, and a second light intensity under the second surface, a ratioof the first light intensity to the second light intensity is in a rangeof 2˜9.

The light-emitting device includes an optic structure with a top surfaceabove the first surface and a bottom surface under the second surface,and the optic structure is pervious to the light from the light-emittingunit.

The following description illustrates embodiments and together withdrawings to provide a further understanding of the disclosure describedabove.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A shows a drawing of a light-emitting device in accordance with anembodiment of the present disclosure.

FIG. 1B shows a top view of a carrier of a light-emitting device shownin FIG. 1A.

FIG. 1C shows a bottom view of a carrier of a light-emitting deviceshown in FIG. 1A.

FIG. 1D shows a cross-sectional view taken along line I-I of FIG. 1B ofa light-emitting device shown in FIG. 1A.

FIG. 1E shows a cross-sectional view of a light-emitting device shown inFIG. 1A.

FIG. 1F shows an enlarged view of FIG. 1E.

FIGS. 2A˜2D respectively show different light emitting routes of thelight-emitting unit within the optic structure.

FIG. 2E shows a luminous intensity distribution curve of alight-emitting device in accordance with an embodiment of the presentdisclosure.

FIG. 3A shows a cross-sectional view of a light-emitting unit inaccordance with an embodiment of the present disclosure.

FIG. 3B shows a cross-sectional view of a light-emitting unit inaccordance with another embodiment of the present disclosure.

FIG. 3C shows a top view of FIG. 3B.

FIG. 3D shows a cross-sectional view of a light-emitting unit inaccordance with another embodiment of the present disclosure.

FIG. 4 shows a drawing of a lamp in accordance with an embodiment of thepresent disclosure.

FIG. 5A shows a manufacturing flow of a light-emitting device inaccordance with an embodiment of the present disclosure.

FIGS. 5B˜5E show drawings of manufacturing a light-emitting device inaccordance with an embodiment of the present disclosure.

DETAILED DESCRIPTION OF THE EMBODIMENTS

The drawings illustrate the embodiments of the application and, togetherwith the description, serve to illustrate the principles of theapplication. The same name or the same reference number given orappeared in different paragraphs or figures along the specificationshould has the same or equivalent meanings while it is once definedanywhere of the disclosure. The thickness or the shape of an element inthe specification can be expanded or narrowed. It is noted that theelements not drawn or described in the figure can be included in thepresent application by the skilled person in the art.

FIG. 1A shows a drawing of a light-emitting device 100 in accordancewith an embodiment of the present disclosure. FIG. 1B shows a top viewof a carrier 11 shown in FIG. 1A. FIG. 1C shows a bottom view of acarrier 11 shown in FIG. 1A. FIG. 1D shows a cross-sectional view takenalong line I-I of FIG. 1B of a light-emitting device shown in FIG. 1A.FIG. 1E shows a cross-sectional view of FIG. 1A along the YZ direction.Referring to FIGS. 1A˜1E, the light-emitting device 100 includes anoptic structure 10, a carrier 11, and a plurality of light-emittingunits 12. The carrier 11 has a top surface 111 and a bottom surface 112.A circuit structure 13 is formed on the top surface 11 and has a firstelectrode pad 131, a second electrode pad 132, and a conductive circuittrace 133. The plurality of light-emitting units 12 is disposed on andconnected in series by the conductive circuit traces 133 which are onthe top surface 111. In other embodiment, the plurality oflight-emitting units 12 is connected in parallel, in series-parallel, orin bridging connection by another type of the conductive circuit traces133. In this embodiment, the light from the plurality of light-emittingunits 12 does not pass through the carrier 11. Therefore, the light fromthe plurality of light-emitting units 12 emits toward the top surface111 but does not pass through the top surface 111. The carrier 11 can bea circuit board. The core layer of the circuit board includes metal,thermoplastic material, thermosetting material, or ceramic material. Themetal includes Al, Cu, Au, Ag, an alloy thereof. Besides, the metal canbe a multilayer structure or a single layer structure. The thermosettingmaterial includes phenolic resin, epoxy, bismaleimide triazine resin, orcombinations thereof. The thermoplastic material includes polyimideresin, polytetrafluorethylene, and so on. The ceramic material includesaluminum oxide, aluminum nitride, aluminum silicon carbide, and so on.

As shown in FIGS. 1A, 1B, and 1C, a reflective layer 14 is formed on thetop surface 111 and the circuit structure 13, and exposes some portionsof the conductive circuit traces 133, which are the exposed conductivecircuit traces 1331, 1332 right under the plurality of light-emittingunits 12 for bonding, and the electrode pads 131, 132. The exposedconductive circuit traces 1331, 1332 are physically separated. In thisembodiment, the conductive circuit trace 1332A close to the electrodepad 131 is physically separated from the electrode pad 131 and theconductive circuit trace 1331B close to the electrode pad 132 isphysically separated from the electrode pad 132. Each of thelight-emitting units 12 has a first connecting pad 120A and a secondconnecting pad 120B electrically and physically connected to the exposedconductive circuit traces 1331, 1332. In this embodiment, the shape ofthe top view of each of exposed conductive circuit traces 1331, 1332 isrectangular and has a long side parallel to that of the carrier 11. Inanother embodiment, the long side of each of exposed conductive circuittraces 1331, 1332 is parallel to the short side of the carrier 11, orhas an angle between 0˜90 degree with the long side of the carrier 11.In another embodiment, the shape of the top view of the exposedconductive traces 1331, 1332 are a round, an ellipse, or a polygon.Additionally, the reflective layer 14 is able to reflect the light fromthe light-emitting unit 12 toward the carrier 11 to increase thelighting efficiency of the light-emitting device 100.

As shown in FIG. 1C and FIG. 1D, the light-emitting unit 12 is notdisposed on the bottom surface 112. The circuit structure 13 furtherincludes a third electrode pad 134 and a fourth electrode pad 135 formedon the bottom surface 112 of the carrier 11. The positions of the thirdelectrode pad 134 and the forth electrode pad 135 correspond to theposition of the first electrode pad 131 and the second electrode pad 132respectively. A first through-hole 151 passes through the carrier 11 andhas a conductive material filled therein partially or entirely forelectrically connecting to the first electrode pad 131 and the thirdelectrode pad 134. A second through-hole 152 passes through the carrier11 and has a conductive material filled therein partially or entirelyfor electrically connecting to the second electrode pad 132 and thefourth electrode pad 135. In one embodiment, the external power (powersupply) can be connected to the first electrode pad 131 and the secondelectrode pad 132 so as to make the plurality of light-emitting units 12emit light. In one embodiment, the third electrode pad 134 and thefourth electrode pad 135 are not physically connected to the externalpower. While the electrode pads 131, 132 are electrically connected tothe external power by resistance welding (soldering), a metal clip isneeded to clip the carrier 11, and the third electrode pad 134 and thefourth electrode pad 135 can make the light-emitting device 100 morerobust and provide a conductive path during the clipping process of thefabrication. In one embodiment, the electrode pads 131, 132 areelectrically connected to the external power by bonding wire and thethird electrode pad 134 and the fourth electrode pad 135 does not needto be formed.

As shown in FIG. 1A and FIG. 1E, the optic structure 10 covers the topsurface 111, the bottom surface 112 of the carrier 11, and the sidesurface 113 of the two long sides of the carrier 11, and exposes theelectrode pads 131, 132, 134, 135. The optic structure 10 has arectangular-like shape in cross-sectional view. FIG. 1F is an enlargedview of FIG. 1E. The optic structure 10 has a top surface 101 with acurved portion; two side surfaces 102 which are substantial straightlines and parallel to each other in the cross-sectional view; twoside-bottom surfaces 103; and a bottom surface 104 which is asubstantial flat surface connecting two side-bottom surface 103. The topsurface 101 is arranged above the top surface 111 of the carrier 11 andthe bottom surface 104 is arranged under the bottom surface 112 of thecarrier 11. The side surface 102 extends from the top surface 101 to thebottom surface 112 of the carrier 11 along z direction. Each side-bottomsurfaces 103 includes a first portion 1031 which extends from the sidesurface 102 to the bottom surface 104 with an inclined angle; and asecond portion 1302. The second portion 1302 located at right side orleft side of the optic structure 10 connects the first portion 1031 andextends curvedly to the bottom surface 104, respectively. The firstdistance (D1) between the bottom surface 112 of the carrier 11 and thebottom surface 104 of the optic structure 10 is of 0.3 mm˜0.7 mm; thesecond distance (D2) between the top surface 111 of the carrier 11 andthe top surface 101 of the optic structure 10 is of 0.8 mm˜0.13 mm. Thesecond distance (D2) is larger than the first distance (D1). The topsurface 101 has a curved portion with a curvature radius of 0.4 mm˜0.7mm, and has a central angle θ₁ of 40°˜60° or a radium of 2π/9˜π/3. Thesecond portion 1302 of the side-bottom surface 103 has a curved portionwith a curvature radius of 0.2˜0.4 mm, and has a central angle θ₂ of5°˜20° or a radium of π/36˜π/9. The diffusing powder (TiO₂, ZrO₂, ZnO,Aluminum oxide) can be optionally filled in the optic structure 10 toimprove the diffusion or/and the scatter of the light from thelight-emitting unit 12. The diffusing powder in the optic structure 10has a weight percentage concentration (w/w) of 0.1˜0.5%, and has aparticle size of 10 nm˜100 nm or 10˜50 μm. In one embodiment, the weightpercentage concentration of the diffusing powder in the gel can bemeasured by the thermogravimetric analyzer (TGA). In brief, during theheating process, the temperature is increased gradually and the gel canbe removed by evaporation of thermal cracking reaction, for example,while the temperature reaches a certain degree so the diffusing powderis remained. Hence, the weight of the gel and the weight of thediffusing powder can be obtained based on the weight difference of themeasuring object, and the weight percentage concentration of thediffusing powder in the gel is determined. Alternatively, the totalweight of the gel and the diffusing powder can be measured first, andwhen the gel is removed by the solvent afterward, the weight of thediffusing powder is measured and the weight percentage concentration ofthe diffusing powder in the gel is obtained. Referring to FIG. 1A,although the plurality of light-emitting units 12 can be seen, the opticstructure 10 would look like white when the concentration of thediffusing powder filled in the optic structure reaches a specific levelso the plurality of light-emitting units 12 cannot be seen.

The optic structure 10 is transparent to light, such as sunlight or thelight from the light-emitting unit 12. The optic structure 10 includessilicone, epoxy, PI, BCB, PFCB, SU8, acrylic resin, PMMA, PET, PC,polyetherimide, fluorocarbon polymer, Al₂O₃, SINR, or SOG.

FIG. 2A shows a light emitting route of the light-emitting unit 12within the optic structure 10. To be more specific, the route shown inthe figure is just one of several possible routes and not a uniqueroute. The following figures are similar to FIG. 2A. For example, thelight (L) from the light-emitting unit 12 emits to the top surface 101and produces a first refracting light (L11) and a first reflecting light(L12) on the top surface 101. The first reflecting light (L12) emits tothe side surface 102 and produces a second refracting light (L21) and asecond reflecting light (L22) on the side surface 102. The secondreflecting light (L22) emits to the bottom surface 104 and produces athird refracting light (L31) and a third reflecting light (L32) on thebottom surface 104. Or, as shown in FIG. 2B, for example, the light (M)from the light-emitting unit 12 emits to the top surface 101 andproduces a first refracting light (M11) and a first reflecting light(M12) on the top surface 101. The first reflecting light (M12) emits tothe first portion 1031 of the side-bottom surface 103 and produces asecond refracting light (M21) and a second reflecting light (L22) on thefirst portion 1031. The second reflecting light (M22) emits to thebottom surface 104 and produces a third refracting light (M31) and athird reflecting light (M32) on the bottom surface 104. FIG. 2C and FIG.2D show other possible light emitting routes within the optic structure10. The probability of the light emitting out of the bottom surface 112of the carrier 10 and out of the bottom surface 104 can be increased bythe geometric design of the optic structure 10 according to the presentdisclosure. The light-emitting device 100 can have a first luminousintensity above the top surface 111 (the first side) and a secondluminous intensity under the bottom surface 112 (the second side), andthe ratio of the first luminous intensity to the second luminousintensity is about of 2˜9. The definition of the first luminousintensity and the second luminous intensity can refer to the followingdescription. To be more specific, the light emitting route shown in thefigure is just one of the several possible routes and is not the onlyroute. Though the light is refracted and reflected on a surfacesimultaneously, the light can also be refracted only or reflected onlydepending on the difference of the refractive index between thematerials, the incident angle, and the wavelength of light at theboundary of materials, etc.

FIG. 2E shows a luminous intensity distribution curve of alight-emitting device 100 operated under an operating current of 10 mAand in a thermal steady state. In more detail, when the light-emittingdevice 100 emits light, an imaginary circle (as the P1 circle shown inFIG. 1A) of the light intensity is measured by the luminous intensitydistribution measuring system. Furthermore, the light intensity of eachpoint on the circle and corresponding angle are plotted to obtain theluminous intensity distribution curve. For measuring purpose, thelight-emitting device 100 has a geometric center at a positioncorresponding to the center of the P1 circle. In this embodiment, theweight percentage concentration of the diffusing powder is 0.3%. Asshown in the figure, the maximum of the light intensity is about 4.53candela (cd); the light intensity from 0° to 180° is substantially alambertian distribution. To be more specific, the light intensity isminimum at −90° and is about 0.5 candela (cd); the light intensity isalmost the same from −90° to −80°; the light intensity from −80° to 90°is gradually increased; the curve in the light intensity from−90°˜0°˜90° is similar to that from 90°˜180°˜−90°; and the lightintensity distribution within a range of angle of −90°˜0°˜90° issymmetrical to that within a range of angle of 90°˜180°˜−90° withrespect to the axis of 90°˜−90°. Furthermore, in the luminous intensitydistribution curve, the overall of the light intensity within a range ofangle of 0°˜90°˜180° is the first light intensity, and the overall ofthe light intensity within a range of angle of 0°˜−90°˜−180° is thesecond light intensity, the ratio of the first light intensity to thesecond light intensity is about 4. The emitting angle of thelight-emitting device 100 calculated from the luminous intensitydistribution curve is about 160°.

The emitting angle is defined as the angular range from the maximumlight intensity down to 50% of the maximum light intensity. For example,a relationship curve (not shown) between light intensity and angle isdrawn using a Cartesian coordinate system (x coordinate representsangle; y coordinate represents light intensity) transformed from theluminous intensity distribution curve (polar diagram) obtained bymeasuring the P1 circle of the light-emitting device 100 of FIG. 2E.Next, a line is plotted whereat the value is 2.265 candela (50% of themaximum light intensity) parallel to the x coordinate to intersect thecurve at two points (two intersections) and an angular range between thetwo points is calculated to obtain the emitting angle.

FIG. 3A shows a cross-sectional view of the light-emitting unit 12A inaccordance with an embodiment of the present disclosure. Thelight-emitting unit 12A includes a light-emitting body 121, a firsttransparent element 122, a phosphor structure 123, a second transparentelement 124, and a third transparent element 125. The light-emittingbody 121 includes a substrate, a first-type semiconductor layer, anactive layer, a second-type semiconductor layer (above is not shown),and two electrodes 1211. When the light-emitting body 121 has ahetero-structure, the first-type semiconductor layer and the second-typesemiconductor layer, for example a cladding layer or a confinementlayer, provide holes and electrons, respectively, and each type layerhas a bandgap greater than that of the active layer, thereby improvingprobability of electrons and holes combining in the active layer to emitlight. The first-type semiconductor layer, the active layer, and thesecond-type semiconductor layer include a semiconductor material ofIII-V group, such as Al_(x)In_(y)Ga_((1-x-y))N orAl_(x)In_(y)Ga_((1-x-y))P with 0≤x,y≤1, (x+y)≤1. According to thematerial of the active layer, the light-emitting body 121 can emit a redlight having a peak wavelength or dominant wavelength between 610˜650nm, a green light having a peak wavelength or dominant wavelengthbetween 530˜570 nm, or a blue light having a peak wavelength or dominantwavelength between 450˜490 nm. The phosphor structure 123 includes aplurality of phosphor particles. The phosphor particle has a particlesize of 5 μm˜100 μm (diameter) and includes one or more than two kindsof phosphor material. The phosphor material includes, but is not limitedto, yellow-greenish phosphor and red phosphor. The yellow-greenishphosphor includes aluminum oxide (such as YAG or TAG), silicate,vanadate, alkaline-earth metal selenide, or metal nitride. The redphosphor includes fluoride (K₂TiF₆:Mn⁴⁺, K₂SiF₆:Mn⁴⁺), silicate,vanadate, alkaline-earth metal sulfide, oxynitride, or a mixture oftungstate and molybdate. The phosphor structure 123 can absorb a firstlight from the light-emitting body 121 to convert to a second light witha peak wavelength different from that of the first light. The firstlight is mixed with the second light to produce a mixing light, such aswhite light. In an embodiment, the light-emitting unit 12 has a whitecolor temperature of 2200K˜6500K (ex. 2200K, 2400K, 2700K, 3000K, 5700K,6500K) and a color point (CIE x, y) is within a seven-step MacAdamellipse, and has a color rendering index (CRI) greater than 80 or 90. Inanother embodiment, the first light can be mixed with the second lightto produce a purple light, yellow light or other non-white light.

The light-emitting unit 12 further includes an insulting layer 126formed under the first transparent element 122, the phosphor structure123, and the second transparent element 124 without covering twoelectrodes 1211 of the light-emitting body 121; and two extendingelectrodes 127 are formed on the electrodes 1211 and electricallyconnected to the two electrodes 1211. Two extending electrodes 127 arethe first connecting pad 120A and the second connecting pad 120Baforementioned (as shown in FIG. 1D). The insulating layer 126 includesa mixture including a matrix and a high reflective material. The matrixincludes silicone-based matrix or epoxy-based matrix. The highreflective material includes titanium oxide, silicon dioxide, oraluminum oxide. Furthermore, the insulating layer 126 has a function ofreflecting the light or diffusing the light. The extending electrodes127 can be a single layer or a multilayer structure, and include metal,such as Cu, Ti, Au, Ni, Ag, or alloy thereof. The first transparentelement 122, the second transparent element 124, and the thirdtransparent element 125 are transparent to light, such as sunlight orthe light from the light-emitting unit 12. The first transparent element122 and the second transparent element 124 include silicone, epoxy, PI,BCB, PFCB, SU8, acrylic resin, PMMA, PET, PC, polyetherimide,fluorocarbon polymer, Al₂O₃, SINR, or SOG. The third transparent element125 includes sapphire, diamond, glass, epoxy, quartz, acrylic resin,SiO_(x), Al₂O₃, ZnO, or silicone.

As shown in FIG. 3A, the third transparent element 125 has a taperedshape. In more detail, the third transparent element 125 has a firstportion 1251 and a second portion 1252. The second portion 1252 iscloser to the second transparent element 124 than the first portion 1251and has a width smaller than that of the first portion 1251. The firstportion 1251 has a thickness 1%˜20% or 1%˜10% of the thickness of thethird transparent element 125. In this embodiment, an intersection wherethe first portion 1251 meets with the second portion 1252 is as an arc.The first portion 1251 has a side surface 1251S slightly inclined toupward (face upward), and is more far away from the side surface of thelight light-emitting body 121 than the side surface 1241 of the secondtransparent element 124 to guide the light to two sides of thelight-emitting unit 12.

In an embodiment, the light-emitting unit 12A is defined as afive-surface (top, left, right, front, and rear) light-emittingstructure and has an emitting angle (beam angle) of about 140°.Alternatively, the diffusing powder can be added in the firsttransparent element 122, and/or the second transparent element 124,and/or the third transparent element 125. In another embodiment, thelight-emitting unit 12A does not include the third transparent element125.

FIG. 3B shows a cross-sectional view of the light-emitting unit 12B inaccordance with another embodiment of the present disclosure. FIG. 3C isa top view of FIG. 3B. The light-emitting unit of FIG. 3B has astructure similar to that of FIG. 3A, wherein devices or elements withsimilar or the same symbols represent those with the same or similarfunctions. As shown in FIG. 3B, the third transparent element 125′ has ashape of frustum with a surface 1253 and an inclined surface 1254. Theinclined surface 1254 can increase the lighting extraction of thelight-emitting body 121 and change the light field of the light-emittingunit 12. The surface 1253 and the inclined surface 1254 have an angle(Φ) between 120°˜150°, and the thickness (H₁) of the inclined surface1254 is 30%˜70% or 40%˜60% of the thickness (H₂) of the thirdtransparent element 125′. As shown in FIG. 3C, the area of theprojecting plane of the surface 1253 (A1; triangle) is 40%˜95% or40%˜60% of that (A; inclined line) of the third transparent element 125.

FIG. 3D shows a cross-sectional view of the light-emitting unit 12D inaccordance with another embodiment of the present disclosure. Thelight-emitting unit of FIG. 3D has a structure similar to that of FIG.3A, wherein devices or elements with similar or the same symbolsrepresent those with the same or similar functions. Light-emitting unit12D further includes a reflective structure 129 formed between the firsttransparent element 124 and the second transparent 125. The reflectivestructure 129 has a reflectivity larger than 85% when the incident lighthas a peak wavelength between 450 nm and 475 nm; or the reflectivestructure 129 has a reflectivity larger than 80% when the incident lighthas a peak wavelength between 400 nm and 600 nm. The light not reflectedby the reflective structure 129 emits into the third transparent element125. If the reflective structure 129 reflects most of the light, forexample, when the reflectivity is more than 95%, the light-emitting unit12D can leave out the third transparent element 125. The reflectivestructure 129 can be a single layer structure or a multiple layersstructure. The single layer structure can be a metal layer or an oxidelayer. The metal layer includes sliver and aluminum, and the oxide layerincludes titanium dioxide. The multiple layers structure can be a stackstructure of metal and metal oxide or a Distributed Bragg Reflector(DBR). The stack structure of metal and metal oxide can be the stack ofaluminum and aluminium oxide. The DBR can be the semiconductor layer ornon-semiconductor layer. The non-semiconductor layer is made of amaterial chosen from the following: Al₂O₃, SiO₂, TiO₂, Nb₂O₅, orSiN_(x). The semiconductor layer is made of a material chosen from thefollowing: GaN, AlGaN, AlInGaN, AlAs, AlGaAs, and GaAs. In thisembodiment, both the single layer structure and the multiple layersstructure do not reflect all amount of the light, hence at least aportion of the light passes through the reflective structure 129.

In another embodiment, the light-emitting unit 12 shown in FIG. 1A has astructure similar to the light-emitting unit 12A, 12B, or 12D shown inFIG. 3A, FIG. 3B, FIG. 3D, but without including the phosphor structure123. Therefore, the light-emitting unit 12 emits the original light fromthe light-emitting body 121, such as red, green, or blue. The pluralityof phosphor particles (wavelength converting materials) is added in theoptic structure 10 to absorb the first light from the light-emittingbody 121 and convert to the second light which is different from thefirst light. Hence, the light-emitting device 100 has a white colortemperature of 2200K˜6500K (ex. 2200K, 2400K, 2700K, 3000K, 5700K,6500K) and a color point (CIE x, y) is within a seven-step MacAdamellipse, and has a color rendering index (CRI) greater than 80 or 90.

The light-emitting unit is disposed on the carrier by the flip chipbonding in this embodiment. In another embodiment, the plurality oflight-emitting units with horizontal type or vertical type (not shown)is fixed on the carrier by the silver paste or the conductivetransparent paste; then, the plurality of light-emitting units iselectrically connected by wire boding; finally, providing an opticstructure to cover the plurality of light-emitting units to form thelight-emitting device.

FIG. 4 shows a drawing of a lamp 30 in accordance with an embodiment ofthe present disclosure. The lamp 30 includes a cover 301, a circuitboard 302, a supporting post 303, a plurality of the light-emittingdevices 100, a thermal dissipating structure 304, and an electricalconnector 305. The plurality of light-emitting devices 100 is fixed andelectrically connected to the supporting post 303. In more detail, anelectrode 307 is formed on the supporting post 303 and electricallyconnected to the circuit board 302. The third electrode pad 134 of eachof the light-emitting device 100 electrically connects the circuit board302 by a metal wire 308. Because the first electrode pad 131 iselectrically connected to the third electrode pad 134, the firstelectrode pad 131 also electrically connects the circuit board 302. Thesecond electrode pad 132 of each of the light-emitting device 100electrically connects the electrode 307 by a metal wire 309. In thisembodiment, according to the electrical connecting way of the foresaid,the plurality of light-emitting devices 100 is connected in parallel. Inanother embodiment, the plurality of light-emitting devices 100 isconnected in series or in series-parallel.

FIG. 5A shows a manufacturing flow of a light-emitting device inaccordance with an embodiment of the present disclosure. As shown inFIG. 5A and FIG. 5B, a holder 21 is provided in step 501. The holder 21includes two frames 211 and a plurality of carriers 11, and theplurality of carriers 11 is arranged between and connected to two frames211. The carrier 11 has a circuit structure 13 which is formed before orafter forming two frames 211 and the carrier 11. For example, two frames211 and the carrier 11 are formed by stamping a unity board, and thecircuit structure 13 can be formed first on that unity board beforestamping or on the carrier 11 after the stamping step. As shown in FIG.5A and FIG. 5C, the plurality of light-emitting units 12 is fixed on thecarrier 11 by surface mount technology (SMT) in the step 502, and theplurality of light-emitting units 12 is electrically connected eachother by the circuit structure 13. As shown in FIG. 5A and FIG. 5D, theoptic structure 10 is formed in the step 503 by molding, such asinjection molding or transfer molding. The light-emitting units 12 andthe carrier 11 are enclosed by the optic structure 10 and the electrodes131, 132 are exposed out of the optic structure 10. As shown in FIG. 5Aand FIG. 5E, the carrier 11 and two frames 211 are separated in the step504 by punching or laser cutting, hence each independent light-emittingdevice 100 can be obtained at the same time or in one step.

It will be apparent to those having ordinary skill in the art thatvarious modifications and variations can be made to the devices inaccordance with the present disclosure without departing from the scopeor spirit of the disclosure. In view of the foregoing, it is intendedthat the present disclosure covers modifications and variations of thisdisclosure provided they fall within the scope of the following claimsand their equivalents.

What is claimed is:
 1. A lamp, comprising: a first carrier comprising afirst portion and a second portion extended from the first portion; anelectrode pad disposed on the first portion; a plurality oflight-emitting units disposed on the second portion; a conductive lineelectrically connecting the electrode pad and at least one of theplurality of light-emitting units; a first reflective layer contactingthe conductive line without covering the plurality of light-emittingunits; an optic structure comprising a wavelength converting material,and contacting the plurality of light-emitting units without coveringthe first portion; and a cover covering the first portion and the secondportion, wherein the first portion is wider than the second portion in atop view.
 2. The lamp according to claim 1, wherein the first carriercomprises a third portion extended from the second portion and exposedfrom the optic structure.
 3. The lamp according to claim 1, wherein theoptic structure covers the conductive line.
 4. The lamp according toclaim 1, further comprising a second carrier which is not parallel tothe first carrier.
 5. The lamp according to claim 4, wherein each of thefirst carrier and the second carrier has a rear surface on which theplurality of light-emitting units is not disposed.
 6. The lamp accordingto claim 5, wherein the cover has a geometric center in a top view, therear surfaces of the first carrier and the second carrier are arrangedto face the geometric center.
 7. The lamp according to claim 4, furthercomprising a supporter inclined with the first carrier and the secondcarrier.
 8. The lamp according to claim 1, wherein the first carrier hasa top surface on which the plurality of light-emitting units is disposedand a rear surface opposite to the top surface, a first light intensitymeasured above the top surface, and a second light intensity measuredunder the rear surface, a ratio of the first light intensity to thesecond light intensity is in a range of 2 to
 9. 9. The lamp according toclaim 1, wherein the first carrier includes a metallic material.
 10. Thelamp according to claim 1, wherein the first carrier includes a ceramicmaterial.
 11. The lamp according to claim 1, wherein the plurality oflight-emitting units is connected in series-parallel.
 12. The lampaccording to claim 1, wherein each of the plurality of light-emittingunit has a light-emitting body and a reflective structure arranged in aconfiguration of reflecting light from the light-emitting body.
 13. Thelamp according to claim 12, wherein each of the plurality oflight-emitting units has a plurality of electrodes, the plurality ofelectrodes and the reflective structure are disposed on opposite sidesof the light-emitting body.
 14. The lamp according to claim 12, furthercomprising a transparent element disposed on the reflective structure.15. The lamp according to claim 1, further comprising a secondreflective layer, wherein the plurality of light-emitting units and thesecond reflective layer are disposed on opposite surfaces of the firstcarrier.